Question

The graph of f(x) = (0.5)x is replaced by the graph of g(x) = (0.5)x − k. If g(x) is obtained by shifting f(x) down by 2 units, then what is the value of k?

k = 2
k equals one half
k = −2
k equals negative one half

Answer 1

Answer: k = 2

Reason:

To shift down 2 units, we go from f(x) = (0.5)x to g(x) = (0.5)x - 2.

The -2 at the end means we subtract 2 from each y coordinate.

Compare this to g(x) = (0.5)x - k to find that k = 2.